1. Field of the Disclosure
The present disclosure relates to a watermark formation element for forming watermarks in paper, a cylinder mould cover comprising such a watermark formation element, a method of making such a cylinder mould cover, a method of making paper using such a cylinder mould cover and paper made thereby.
2. Description of the Related Art
The use of watermarks is fairly common in many security documents. High security multi-tonal watermarks are typically created using a cylinder mould process and these are commonly known as cylinder mould watermarks. Cylinder mould watermarks are formed by varying the density of paper fibres so that in some regions the fibres are denser, and in others less dense, than that of the base paper layer which surrounds and separates the denser and less dense regions. When viewed in transmitted light the less dense regions are lighter and the denser regions darker than the base paper and the contrasts can be seen very clearly. Different types of watermarks have different advantages. A cylinder mould watermark, usually formed on an embossed cylinder mould cover, is often a pictorial image, such as a portrait, and can be very detailed and complex which significantly reduces the risk of counterfeiting.